THE PAST PERFECT TENSE

A. Use:

The Past Perfect tense is used to refer to a non-continuous action in
the past, which was already completed by the time another action in the past
took place. Notice that Simple past and Past perfect are generally used together with conjuctions like when, after, before and until.
The Past perfect refers to the first action and Simple past to the second action.

--> She had heard the news before I saw her.--> I had finished my work by the time the clock struck
twelve.

In the preceding examples, the verbs had heard and had
finished are in the Past Perfect tense, and the verbs saw and
struck are in the Simple Past. The use of the Past Perfect tense
indicates that the actions of hearing the news and finishing the work were
already completed by the time the actions expressed by the verbs in the Simple
Past took place.

b. Formation:

The Past Perfect
tense is formed from the Simple Past of the auxiliary to have, followed
by the past participle of the verb.

The Simple Past of to have is
had. In spoken English, the auxiliary had is often contracted to
'd. For example, the Past Perfect of the verb to work is
conjugated as follows:

Without Contractions

With Contractions

I had worked

I'd worked

you had worked

you'd worked

he had worked

he'd worked

she had worked

she'd worked

it had worked

it'd worked

we had worked

we'd worked

they had worked

they'd worked

The
contraction it'd is less frequently used than the other contractions,
since it is more difficult to pronounce.

c. Questions and negative statements:

As
is the case with other English tenses, questions and negative statements in the
Past Perfect tense are formed using the auxiliary.

Questions are formed
by placing the auxiliary before the subject. For example:

Affirmative Statement

Question

I had worked.

Had I worked?

They had worked.

Had they worked?

Negative statements are
formed by placing the word not after the auxiliary. For example:

Affirmative Statement

Negative Statement

I had worked.

I had not worked.

They had worked.

They had not worked.

In
spoken English, the following contraction is often used:

Without Contraction

With Contraction

had not

hadn't

Negative questions are formed by
placing the auxiliary before the subject, and the word not after the
subject. However, when contractions are used, the contracted form of not
follows immediately after the auxiliary. For example: